High voltage power supplies (voltages >100 V) are essential to such technologies as Radar, X-ray inspection, Cancer therapy, Corona processing, Semiconductor Fabrication, and a variety of other important fields. In creating a high voltage power supply using existing inverter topologies such as the Cuk converter, there are problems due to the energy in the stray capacitance, and due to insulation in the presence of a magnetic core. The core distances in a DC power supply—particularly at high voltage—are all constrained because the leakage inductance of the system must be small, and distance increases inductance since the field energy between windings depends on the distance between windings.
An ideal system would allow for increased insulation, reductions in the core material used, and improved handing of the capacitive energy stored between the primary and the secondary. Operation with reduced coupling coefficient has been described by Abramyan in the unique case of pulse charging of output capacitances. Details of such transformer designs have been proposed—for example by Crewson. Adler showed how to use loosely coupled transformers in a very specific application. A general method of creating improved high voltage power supplies would be desirable.